1. Technical Field
Embodiments of the present invention relate to an image forming apparatus functioning as a copier, a printer, a facsimile machine, or a multifunctional system having at least two features of the copier, the printer, and the facsimile machine.
2. Related Art
A fixing unit of a heat and pressure application method is employed to image forming apparatuses. The fixing unit fixes a toner image to a recording medium conveyed to a fixing nip area provided therein by heating and fusing the toner image held on the recording medium with application of heat and pressure.
However, in the fixing unit during this fixing operation, moisture contained in the recording medium evaporates due to heat application. Heated steam dew-condenses on a conveying guide and/or a conveying roller, which produces water droplet. In this case, the water droplet can adhere to the recording medium. For example, if the stream generated by the fixing unit dew-condenses on the conveying guide disposed above the fixing unit, when a duplex printing is performed, the water droplet produced by dew-condensation on the conveying guide adheres to the recording medium. Consequently, the water droplet disorders a toner image to be transferred onto the back side of the recording medium, resulting in image formation failure such as a total or partial loss of image data.
To address this problem, typical image forming apparatuses include a condensation occurrence part to intentionally condense steam generated in the image forming apparatus. The condensation occurrence part is disposed at a position different from a sheet conveying path to collect water droplet produced in the condensation occurrence part to a recovery container.
For example, Japanese Patent Application Publication No. JP-2011-059483-A discloses a configuration including a condensation member to positively dew-condense moisture in the air and a recovery container to collect or recover water droplet produced with the condensation member in an adjacent area to a conveying path through which a recording medium is conveyed. The condensation member has a slope on which the condensed water droplet moves along with an aid of gravity in a direction to separate from the conveying path, so that the slope guides the water droplet to the recovery container.
Japanese Patent Application Publication No. JP-H05-035153-A discloses a configuration including a cover that is disposed in a slanted manner. The slanted cover guides water droplet produced by dew-condensation on an inner surface of a cover of a fixing unit to a water droplet recovery portion (a recessed part) formed on the cover.
Japanese Patent Application Publication No. JP-H11-296008-A discloses a configuration including a frame that covers a fixing unit from above. The frame is provided with a film thereon to condense steam or moisture, and also with a dent or a recessed part thereon to store or contain water droplet that falls from the film.
Japanese Patent No. JP-2664313-B (JP-H06-027844-A) discloses a configuration including a partition frame having a slanted surface and being disposed above a fixing and conveying device. The slanted surface of the partition guides water droplet to a recovery container (a recessed part) of a water droplet recovery member to recover and store the water droplet therein. The water droplet recovery member is detachably attached to a fixing unit housing, so that the recover container can be cleaned.
As described above, with the configuration in which steam is dew-condensed in an image forming apparatus and water droplet produced by dew-condensation is stored in a recovery container, it is preferable that the water droplet contained in the recovery container is removed to avoid spilling from the recovery container when the recovery container is in a full state.
However, in the above-described configurations, it is difficult or bothersome for users or operators to remove the water droplet from the recovery container and perform maintenance work such as checking the state of the recovery container from outside the image forming apparatus.